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<meta name="description" content="C# 运算符   运算符是一种告诉编译器执行特定的数学或逻辑操作的符号。C# 有丰富的内置运算符，分类如下：  算术运算符 关系运算符 逻辑运算符 位运算符 赋值运算符 其他运算符  本教程将逐一讲解算术运算符、关系运算符、逻辑运算符、位运算符、赋值运算符及其他运算符。   算术运算符 下表显示了 C# 支持的所有算术运算符。假设变量 A 的值为 10，变量 B 的值为 20，则：  运算符描述实例 +把两个操作数相加 A + B 将得..">
		
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			<h1>C# <span class="color_h1">运算符</span></h1>

<div class="tutintro">
<p>运算符是一种告诉编译器执行特定的数学或逻辑操作的符号。C# 有丰富的内置运算符，分类如下：</p>
<ul class="list">
<li>算术运算符</li>
<li>关系运算符</li>
<li>逻辑运算符</li>
<li>位运算符</li>
<li>赋值运算符</li>
<li>其他运算符</li>
</ul>
<p>本教程将逐一讲解算术运算符、关系运算符、逻辑运算符、位运算符、赋值运算符及其他运算符。</p>
</div>

<h2 class="tutheader">算术运算符</h2>
<p>下表显示了 C# 支持的所有算术运算符。假设变量 <b>A</b> 的值为 10，变量 <b>B</b> 的值为 20，则：</p>
<table class="reference notranslate">
<tr><th style="width:10%">运算符</th><th style="width:55%;">描述</th><th>实例</th></tr>
<tr><td>+</td><td>把两个操作数相加</td><td> A + B 将得到 30</td></tr>
<tr><td>-</td><td>从第一个操作数中减去第二个操作数</td><td> A - B 将得到 -10</td></tr>
<tr><td>*</td><td>把两个操作数相乘</td><td> A * B 将得到 200</td></tr>
<tr><td>/</td><td>分子除以分母</td><td> B / A 将得到 2</td></tr>
<tr><td>%</td><td>取模运算符，整除后的余数</td><td> B % A 将得到 0</td></tr>
<tr><td>++</td><td>自增运算符，整数值增加 1</td><td> A++ 将得到 11</td></tr>
<tr><td>--</td><td>自减运算符，整数值减少 1</td><td> A-- 将得到 9</td></tr>
</table>
<h3>实例</h3>
<p>请看下面的实例，了解 C# 中所有可用的算术运算符：</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">

<span style="color: #05a; font-weight: bold;">using</span> <span style="color: #696969;">System</span><span style="color: #008000;">;</span><br />
<br />
<span style="color: #05a; font-weight: bold;">namespace</span> OperatorsAppl<br />
<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">class</span> Program<br />
&nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">static</span> <span style="color: #6666cc; font-weight: bold;">void</span> Main<span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#91;</span><span style="color: #008000;">&#93;</span> args<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> a <span style="color: #008000;">=</span> <span style="color: Maroon;">21</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> b <span style="color: #008000;">=</span> <span style="color: Maroon;">10</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> c<span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">=</span> a <span style="color: #008000;">+</span> b<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 1 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">=</span> a <span style="color: #008000;">-</span> b<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 2 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">=</span> a <span style="color: #008000;">*</span> b<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 3 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">=</span> a <span style="color: #008000;">/</span> b<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 4 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">=</span> a <span style="color: #008000;">%</span> b<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 5 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// ++a 先进行自增运算再赋值</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">=</span> <span style="color: #008000;">++</span>a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 6 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// 此时 a 的值为 22</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// --a 先进行自减运算再赋值</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">=</span> <span style="color: #008000;">--</span>a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 7 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
<span style="color: #008000;">&#125;</span><br />

</div>
</div>
<p>当上面的代码被编译和执行时，它会产生下列结果：</p>
<pre class="result">
Line 1 - c 的值是 31
Line 2 - c 的值是 11
Line 3 - c 的值是 210
Line 4 - c 的值是 2
Line 5 - c 的值是 1
Line 6 - c 的值是 22
Line 7 - c 的值是 21
</pre>
<ul>
<li><strong>c = a++</strong>: 先将 a 赋值给 c，再对 a 进行自增运算。</li>
<li><strong>c = ++a</strong>: 先将 a 进行自增运算，再将 a 赋值给 c 。</li>
<li><strong>c = a--</strong>: 先将 a 赋值给 c，再对 a 进行自减运算。</li>
<li><strong>c = --a</strong>: 先将 a 进行自减运算，再将 a 赋值给 c 。</li>
</ul>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">

<span style="color: #05a; font-weight: bold;">using</span> <span style="color: #696969;">System</span><span style="color: #008000;">;</span><br />
<br />
<span style="color: #05a; font-weight: bold;">namespace</span> OperatorsAppl<br />
<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">class</span> Program<br />
&nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">static</span> <span style="color: #6666cc; font-weight: bold;">void</span> Main<span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#91;</span><span style="color: #008000;">&#93;</span> args<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> a <span style="color: #008000;">=</span> <span style="color: Maroon;">1</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> b<span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// a++ 先赋值再进行自增运算</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; b <span style="color: #008000;">=</span> a<span style="color: #008000;">++;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;a = {0}&quot;</span>, a<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;b = {0}&quot;</span>, b<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// ++a 先进行自增运算再赋值</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; a <span style="color: #008000;">=</span> <span style="color: Maroon;">1</span><span style="color: #008000;">;</span> <span style="color: #696969; font-style: italic;">// 重新初始化 a</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; b <span style="color: #008000;">=</span> <span style="color: #008000;">++</span>a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;a = {0}&quot;</span>, a<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;b = {0}&quot;</span>, b<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// a-- 先赋值再进行自减运算</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; a <span style="color: #008000;">=</span> <span style="color: Maroon;">1</span><span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 重新初始化 a</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; b<span style="color: #008000;">=</span> a<span style="color: #008000;">--;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;a = {0}&quot;</span>, a<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;b = {0}&quot;</span>, b<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// --a 先进行自减运算再赋值</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; a <span style="color: #008000;">=</span> <span style="color: Maroon;">1</span><span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 重新初始化 a</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; b<span style="color: #008000;">=</span> <span style="color: #008000;">--</span>a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;a = {0}&quot;</span>, a<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;b = {0}&quot;</span>, b<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
<span style="color: #008000;">&#125;</span><br />

</div>
<br>
<a target="_blank" href="../try/runcode.php?filename=csharp_inc_des_ope&type=cs" class="showbtn" rel="noopener">运行实例 »</a></p>
</div><p>

<p>执行以上程序，输出结果为：</p>
<pre>
a = 2
b = 1
a = 2
b = 2
a = 0
b = 1
a = 0
b = 0
</pre>
<h2 class="tutheader">关系运算符</h2>
<p>下表显示了 C# 支持的所有关系运算符。假设变量 <b>A</b> 的值为 10，变量 <b>B</b> 的值为 20，则：</p>
<table class="reference notranslate">
<tr><th style="width:10%">运算符</th><th style="width:55%;">描述</th><th>实例</th></tr>
<tr><td>==</td><td>检查两个操作数的值是否相等，如果相等则条件为真。</td><td> (A == B) 不为真。 </td></tr>
<tr><td>!=</td><td>检查两个操作数的值是否相等，如果不相等则条件为真。</td><td> (A != B) 为真。 </td></tr>
<tr><td>&gt;</td><td>检查左操作数的值是否大于右操作数的值，如果是则条件为真。</td><td> (A &gt; B) 不为真。</td></tr>
<tr><td>&lt;</td><td>检查左操作数的值是否小于右操作数的值，如果是则条件为真。</td><td> (A &lt; B) 为真。</td></tr>
<tr><td>&gt;=</td><td>检查左操作数的值是否大于或等于右操作数的值，如果是则条件为真。</td><td> (A &gt;= B) 不为真。</td></tr>
<tr><td>&lt;=</td><td>检查左操作数的值是否小于或等于右操作数的值，如果是则条件为真。</td><td> (A &lt;= B) 为真。</td></tr>
</table>
<h3>实例</h3>
<p>请看下面的实例，了解 C# 中所有可用的关系运算符：</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">

<span style="color: #05a; font-weight: bold;">using</span> <span style="color: #696969;">System</span><span style="color: #008000;">;</span><br />
<br />
<span style="color: #6666cc; font-weight: bold;">class</span> Program<br />
<span style="color: #008000;">&#123;</span><br />
&nbsp; <span style="color: #05a; font-weight: bold;">static</span> <span style="color: #6666cc; font-weight: bold;">void</span> Main<span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#91;</span><span style="color: #008000;">&#93;</span> args<span style="color: #008000;">&#41;</span><br />
&nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> a <span style="color: #008000;">=</span> <span style="color: Maroon;">21</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> b <span style="color: #008000;">=</span> <span style="color: Maroon;">10</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">if</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">==</span> b<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 1 - a 等于 b&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">else</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 1 - a 不等于 b&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">if</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">&lt;</span> b<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 2 - a 小于 b&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">else</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 2 - a 不小于 b&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">if</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">&gt;</span> b<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 3 - a 大于 b&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">else</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 3 - a 不大于 b&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">/* 改变 a 和 b 的值 */</span><br />
&nbsp; &nbsp; &nbsp; a <span style="color: #008000;">=</span> <span style="color: Maroon;">5</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; b <span style="color: #008000;">=</span> <span style="color: Maroon;">20</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">if</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">&lt;=</span> b<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 4 - a 小于或等于 b&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">if</span> <span style="color: #008000;">&#40;</span>b <span style="color: #008000;">&gt;=</span> a<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 5 - b 大于或等于 a&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; <span style="color: #008000;">&#125;</span><br />
<span style="color: #008000;">&#125;</span><br />

</div>
</div>
<p>当上面的代码被编译和执行时，它会产生下列结果：</p>
<pre class="result">
Line 1 - a 不等于 b
Line 2 - a 不小于 b
Line 3 - a 大于 b
Line 4 - a 小于或等于 b
Line 5 - b 大于或等于 a
</pre>

<h2 class="tutheader">逻辑运算符</h2>
<p>下表显示了 C# 支持的所有逻辑运算符。假设变量 <b>A</b> 为布尔值 true，变量 <b>B</b> 为布尔值 false，则：</p>
<table class="reference notranslate">
<tr><th style="width:10%">运算符</th><th style="width:55%;">描述</th><th>实例</th></tr>
<tr><td>&amp;&amp;</td><td>称为逻辑与运算符。如果两个操作数都非零，则条件为真。</td><td> (A &amp;&amp; B) 为假。</td></tr>
<tr><td>||</td><td>称为逻辑或运算符。如果两个操作数中有任意一个非零，则条件为真。</td><td> (A || B) 为真。</td></tr>
<tr><td>!</td><td>称为逻辑非运算符。用来逆转操作数的逻辑状态。如果条件为真则逻辑非运算符将使其为假。</td><td> !(A &amp;&amp; B) 为真。</td></tr>
</table>
<h3>实例</h3>
<p>请看下面的实例，了解 C# 中所有可用的逻辑运算符：</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">

<span style="color: #05a; font-weight: bold;">using</span> <span style="color: #696969;">System</span><span style="color: #008000;">;</span><br />
<br />
<span style="color: #05a; font-weight: bold;">namespace</span> OperatorsAppl<br />
<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">class</span> Program<br />
&nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">static</span> <span style="color: #6666cc; font-weight: bold;">void</span> Main<span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#91;</span><span style="color: #008000;">&#93;</span> args<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">bool</span> a <span style="color: #008000;">=</span> <span style="color: #05a; font-weight: bold;">true</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">bool</span> b <span style="color: #008000;">=</span> <span style="color: #05a; font-weight: bold;">true</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">if</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">&amp;&amp;</span> b<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 1 - 条件为真&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">if</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">||</span> b<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 2 - 条件为真&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">/* 改变 a 和 b 的值 */</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; a <span style="color: #008000;">=</span> <span style="color: #05a; font-weight: bold;">false</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; b <span style="color: #008000;">=</span> <span style="color: #05a; font-weight: bold;">true</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">if</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">&amp;&amp;</span> b<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 3 - 条件为真&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">else</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 3 - 条件不为真&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">if</span> <span style="color: #008000;">&#40;</span><span style="color: #008000;">!</span><span style="color: #008000;">&#40;</span>a <span style="color: #008000;">&amp;&amp;</span> b<span style="color: #008000;">&#41;</span><span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 4 - 条件为真&quot;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
<span style="color: #008000;">&#125;</span><br />

</div>
</div>
<p>当上面的代码被编译和执行时，它会产生下列结果：</p>
<pre class="result">
Line 1 - 条件为真
Line 2 - 条件为真
Line 3 - 条件不为真
Line 4 - 条件为真
</pre>

<h2 class="tutheader">位运算符</h2>
<p>位运算符作用于位，并逐位执行操作。&amp;、 | 和 ^ 的真值表如下所示：</p>
<table class="reference notranslate">
<tr><th style="width:20%">p</th><th style="width:20%">q</th><th style="width:20%">p &amp; q</th><th style="width:20%">p | q</th><th style="width:20%">p ^ q</th></tr>
<tr><td>0</td><td>0</td><td>0</td><td>0</td><td>0</td></tr>
<tr><td>0</td><td>1</td><td>0</td><td>1</td><td>1</td></tr>
<tr><td>1</td><td>1</td><td>1</td><td>1</td><td>0</td></tr>
<tr><td>1</td><td>0</td><td>0</td><td>1</td><td>1</td></tr>
</table>
<p>假设如果 A = 60，且 B = 13，现在以二进制格式表示，它们如下所示：</p>
<p>A = 0011 1100</p>
<p>B = 0000 1101</p>
<p>-----------------</p>
<p>A&amp;B = 0000 1100</p>
<p>A|B = 0011 1101</p>
<p>A^B = 0011 0001</p>
<p>~A&nbsp; = 1100 0011</p>
<p>下表列出了 C# 支持的位运算符。假设变量 <b>A</b> 的值为 60，变量 <b>B</b> 的值为 13，则：</p>
<table class="reference notranslate">
<tr><th style="width:10%">运算符</th><th style="width:55%;">描述</th><th>实例</th></tr>
<tr><td>&amp;</td><td>如果同时存在于两个操作数中，二进制 AND 运算符复制一位到结果中。</td><td> (A &amp; B) 将得到 12，即为 0000 1100</td></tr>
<tr><td>|</td><td>如果存在于任一操作数中，二进制 OR 运算符复制一位到结果中。</td><td> (A | B) 将得到 61，即为 0011 1101</td></tr>
<tr><td>^</td><td>如果存在于其中一个操作数中但不同时存在于两个操作数中，二进制异或运算符复制一位到结果中。</td><td> (A ^ B) 将得到 49，即为 0011 0001</td></tr>
<tr><td>~</td><td>按位取反运算符是一元运算符，具有"翻转"位效果，即0变成1，1变成0，包括符号位。</td><td>(~A ) 将得到 -61，即为 1100 0011，一个有符号二进制数的补码形式。</td></tr>
<tr><td>&lt;&lt;</td><td>二进制左移运算符。左操作数的值向左移动右操作数指定的位数。</td><td> A &lt;&lt; 2 将得到 240，即为 1111 0000</td></tr>
<tr><td>&gt;&gt;</td><td>二进制右移运算符。左操作数的值向右移动右操作数指定的位数。</td><td> A &gt;&gt; 2 将得到 15，即为 0000 1111</td></tr>
</table>
<h3>实例</h3>
<p>请看下面的实例，了解 C# 中所有可用的位运算符：</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">

<span style="color: #05a; font-weight: bold;">using</span> <span style="color: #696969;">System</span><span style="color: #008000;">;</span><br />
<span style="color: #05a; font-weight: bold;">namespace</span> OperatorsAppl<br />
<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">class</span> Program<br />
&nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">static</span> <span style="color: #6666cc; font-weight: bold;">void</span> Main<span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#91;</span><span style="color: #008000;">&#93;</span> args<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> a <span style="color: #008000;">=</span> <span style="color: Maroon;">60</span><span style="color: #008000;">;</span> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #696969; font-style: italic;">/* 60 = 0011 1100 */</span> &nbsp;<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> b <span style="color: #008000;">=</span> <span style="color: Maroon;">13</span><span style="color: #008000;">;</span> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #696969; font-style: italic;">/* 13 = 0000 1101 */</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> c <span style="color: #008000;">=</span> <span style="color: Maroon;">0</span><span style="color: #008000;">;</span> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;c <span style="color: #008000;">=</span> a <span style="color: #008000;">&amp;</span> b<span style="color: #008000;">;</span> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">/* 12 = 0000 1100 */</span> <br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 1 - c 的值是 {0}&quot;</span>, c <span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;c <span style="color: #008000;">=</span> a <span style="color: #008000;">|</span> b<span style="color: #008000;">;</span> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">/* 61 = 0011 1101 */</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 2 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;c <span style="color: #008000;">=</span> a <span style="color: #008000;">^</span> b<span style="color: #008000;">;</span> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">/* 49 = 0011 0001 */</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 3 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;c <span style="color: #008000;">=</span> ~a<span style="color: #008000;">;</span> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">/*-61 = 1100 0011 */</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 4 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;c <span style="color: #008000;">=</span> a <span style="color: #008000;">&lt;&lt;</span> <span style="color: Maroon;">2</span><span style="color: #008000;">;</span> &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">/* 240 = 1111 0000 */</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 5 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;c <span style="color: #008000;">=</span> a <span style="color: #008000;">&gt;&gt;</span> <span style="color: Maroon;">2</span><span style="color: #008000;">;</span> &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">/* 15 = 0000 1111 */</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 6 - c 的值是 {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
<span style="color: #008000;">&#125;</span><br />

</div>
</div>
<p>当上面的代码被编译和执行时，它会产生下列结果：</p>
<pre class="result">
Line 1 - c 的值是 12
Line 2 - c 的值是 61
Line 3 - c 的值是 49
Line 4 - c 的值是 -61
Line 5 - c 的值是 240
Line 6 - c 的值是 15
</pre>

<h2 class="tutheader">赋值运算符</h2>
<p>下表列出了 C# 支持的赋值运算符：</p>
<table class="reference notranslate">
<tr><th style="width:10%">运算符</th><th style="width:55%;">描述</th><th>实例</th></tr>
<tr><td>=</td><td>简单的赋值运算符，把右边操作数的值赋给左边操作数</td><td> C = A + B 将把 A + B 的值赋给 C</td></tr>
<tr><td>+=</td><td>加且赋值运算符，把右边操作数加上左边操作数的结果赋值给左边操作数</td><td> C += A 相当于 C = C + A</td></tr>
<tr><td>-=</td><td>减且赋值运算符，把左边操作数减去右边操作数的结果赋值给左边操作数</td><td> C -= A 相当于 C = C - A</td></tr>
<tr><td>*=</td><td>乘且赋值运算符，把右边操作数乘以左边操作数的结果赋值给左边操作数</td><td> C *= A 相当于 C = C * A</td></tr>
<tr><td>/=</td><td>除且赋值运算符，把左边操作数除以右边操作数的结果赋值给左边操作数</td><td> C /= A 相当于 C = C / A</td></tr>
<tr><td>%=</td><td>求模且赋值运算符，求两个操作数的模赋值给左边操作数</td><td> C %= A 相当于 C = C % A</td></tr>
<tr><td>&lt;&lt;=</td><td>左移且赋值运算符</td><td> C &lt;&lt;= 2 等同于 C = C &lt;&lt; 2</td></tr>
<tr><td>&gt;&gt;=</td><td>右移且赋值运算符</td><td> C &gt;&gt;= 2 等同于 C = C &gt;&gt; 2</td></tr>
<tr><td>&amp;=</td><td>按位与且赋值运算符</td><td> C &amp;= 2 等同于 C = C &amp; 2</td></tr>
<tr><td>^=</td><td>按位异或且赋值运算符</td><td> C ^= 2 等同于 C = C ^ 2</td></tr>
<tr><td>|=</td><td>按位或且赋值运算符</td><td> C |= 2 等同于 C = C | 2</td></tr>
</table>
<h3>实例</h3>
<p>请看下面的实例，了解 C# 中所有可用的赋值运算符：</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">

<span style="color: #05a; font-weight: bold;">using</span> <span style="color: #696969;">System</span><span style="color: #008000;">;</span><br />
<br />
<span style="color: #05a; font-weight: bold;">namespace</span> OperatorsAppl<br />
<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">class</span> Program<br />
&nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">static</span> <span style="color: #6666cc; font-weight: bold;">void</span> Main<span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#91;</span><span style="color: #008000;">&#93;</span> args<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> a <span style="color: #008000;">=</span> <span style="color: Maroon;">21</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #6666cc; font-weight: bold;">int</span> c<span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">=</span> a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 1 - = &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">+=</span> a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 2 - += c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">-=</span> a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 3 - -= &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">*=</span> a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 4 - *= &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">/=</span> a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 5 - /= &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">=</span> <span style="color: Maroon;">200</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">%=</span> a<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 6 - %= &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">&lt;&lt;=</span> <span style="color: Maroon;">2</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 7 - &lt;&lt;= &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">&gt;&gt;=</span> <span style="color: Maroon;">2</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 8 - &gt;&gt;= &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">&amp;=</span> <span style="color: Maroon;">2</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 9 - &amp;= &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">^=</span> <span style="color: Maroon;">2</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 10 - ^= &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c <span style="color: #008000;">|=</span> <span style="color: Maroon;">2</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;Line 11 - |= &nbsp;c 的值 = {0}&quot;</span>, c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
<span style="color: #008000;">&#125;</span><br />

</div>
</div>
<p>当上面的代码被编译和执行时，它会产生下列结果：</p>
<pre class="result">
Line 1 - =     c 的值 = 21
Line 2 - +=    c 的值 = 42
Line 3 - -=    c 的值 = 21
Line 4 - *=    c 的值 = 441
Line 5 - /=    c 的值 = 21
Line 6 - %=    c 的值 = 11
Line 7 - &lt;&lt;=    c 的值 = 44
Line 8 - &gt;&gt;=    c 的值 = 11
Line 9 - &amp;=    c 的值 = 2
Line 10 - ^=    c 的值 = 0
Line 11 - |=    c 的值 = 2
</pre>

<h2 class="tutheader">其他运算符</h2>
<p>下表列出了 C# 支持的其他一些重要的运算符，包括 <b>sizeof</b>、<b>typeof</b> 和 <b>? :</b>。</p>
<table class="reference">
<tr><th style="width:10%">运算符</th><th style="width:55%;">描述</th><th>实例</th></tr>
<tr>
<td>sizeof()</td><td>返回数据类型的大小。</td><td>sizeof(int)，将返回 4.</td>
</tr>
<tr>
<td>typeof()</td><td>返回 class 的类型。</td><td>typeof(StreamReader);</td>
</tr>
<tr>
<td>&amp;</td><td>返回变量的地址。</td><td>&amp;a; 将得到变量的实际地址。</td>
</tr>
<tr>
<td>*</td><td>变量的指针。</td><td>*a; 将指向一个变量。</td>
</tr>
<tr>
<td>? :</td><td>条件表达式</td><td> 如果条件为真 ? 则为 X : 否则为 Y</td>
</tr>
<tr>
<td>is</td><td>判断对象是否为某一类型。</td><td>If( Ford is Car)  // 检查 Ford 是否是 Car 类的一个对象。</td>
</tr>
<tr>
<td>as</td><td>强制转换，即使转换失败也不会抛出异常。</td><td>Object obj = new StringReader("Hello");<br>    
StringReader r = obj as StringReader;
</td>
</tr>
</table>
<h3>实例</h3>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">

<span style="color: #05a; font-weight: bold;">using</span> <span style="color: #696969;">System</span><span style="color: #008000;">;</span><br />
<br />
<span style="color: #05a; font-weight: bold;">namespace</span> OperatorsAppl<br />
<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; <br />
&nbsp; &nbsp;<span style="color: #6666cc; font-weight: bold;">class</span> Program<br />
&nbsp; &nbsp;<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">static</span> <span style="color: #6666cc; font-weight: bold;">void</span> Main<span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#91;</span><span style="color: #008000;">&#93;</span> args<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #696969; font-style: italic;">/* sizeof 运算符的实例 */</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;int 的大小是 {0}&quot;</span>, <span style="color: #008000;">sizeof</span><span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">int</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;short 的大小是 {0}&quot;</span>, <span style="color: #008000;">sizeof</span><span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">short</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;double 的大小是 {0}&quot;</span>, <span style="color: #008000;">sizeof</span><span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">double</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #696969; font-style: italic;">/* 三元运算符的实例 */</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #6666cc; font-weight: bold;">int</span> a, b<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;a <span style="color: #008000;">=</span> <span style="color: Maroon;">10</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;b <span style="color: #008000;">=</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">==</span> <span style="color: Maroon;">1</span><span style="color: #008000;">&#41;</span> <span style="color: #008000;">?</span> <span style="color: Maroon;">20</span> <span style="color: #008000;">:</span> <span style="color: Maroon;">30</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;b 的值是 {0}&quot;</span>, b<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;b <span style="color: #008000;">=</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">==</span> <span style="color: Maroon;">10</span><span style="color: #008000;">&#41;</span> <span style="color: #008000;">?</span> <span style="color: Maroon;">20</span> <span style="color: #008000;">:</span> <span style="color: Maroon;">30</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;b 的值是 {0}&quot;</span>, b<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp;<span style="color: #008000;">&#125;</span><br />
<span style="color: #008000;">&#125;</span><br />

</div>
</div>
<p>当上面的代码被编译和执行时，它会产生下列结果：</p>
<pre class="result">
int 的大小是 4
short 的大小是 2
double 的大小是 8
b 的值是 30
b 的值是 20
</pre>
<p>typeof 关键字用于获取一个类型的类型对象，它通常用于反射和动态创建类型实例。</p>

<p>下面是一个使用 typeof 的简单示例：</p>

<div class="example"><h2 class="example">实例</h2> <div class="example_code">
<span style="color: #05a; font-weight: bold;">using</span> <span style="color: #696969;">System</span><span style="color: #008000;">;</span><br />
<br />
<span style="color: #6666cc; font-weight: bold;">class</span> Program<br />
<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">static</span> <span style="color: #6666cc; font-weight: bold;">void</span> Main<span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#91;</span><span style="color: #008000;">&#93;</span> args<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; Type type <span style="color: #008000;">=</span> <span style="color: #008000;">typeof</span><span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span>type<span style="color: #008000;">.</span><span style="color: #05a;">FullName</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadKey</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
<span style="color: #008000;">&#125;</span><br />
</div></div>
<p>在上面的代码中，我们使用 typeof 关键字来获取 string 类型的类型对象，并将其存储在 Type 类型的变量 type 中，然后，我们使用 FullName 属性打印该类型的完全限定名。</p>
<p>当上面的代码被编译和执行时，它会产生下列结果：</p>
<pre>System.String</pre>


<h2 class="tutheader">C# 中的运算符优先级</h2>
<p>运算符的优先级确定表达式中项的组合。这会影响到一个表达式如何计算。某些运算符比其他运算符有更高的优先级，例如，乘除运算符具有比加减运算符更高的优先级。</p>
<p>例如 x = 7 + 3 * 2，在这里，x 被赋值为 13，而不是 20，因为运算符 * 具有比 + 更高的优先级，所以首先计算乘法 3*2，然后再加上 7。</p>
 <p>下表将按运算符优先级从高到低列出各个运算符，具有较高优先级的运算符出现在表格的上面，具有较低优先级的运算符出现在表格的下面。在表达式中，较高优先级的运算符会优先被计算。<p></p>
<strong>优先级简易概括</strong>：有括号先括号，后乘除在加减，然后位移再关系，逻辑完后条件，最后一个逗号 <span class="marked">,</span> 。</p>
<table class="reference notranslate">
<tr> <th>类别&nbsp;</th> <th>运算符&nbsp;</th><th>结合性&nbsp;</th> </tr> 
<tr> <td>后缀&nbsp;</td><td>() [] -&gt; .  ++   - - &nbsp;</td> <td>从左到右&nbsp;</td> </tr>
<tr> <td>一元&nbsp;</td> <td>+  -   !  ~  ++  - -   (type)*  &amp;  sizeof&nbsp;</td> <td>从右到左&nbsp;</td></tr> 
<tr> <td>乘除&nbsp;</td> <td>*  /  %&nbsp;</td><td>从左到右&nbsp;</td> </tr> 
<tr> <td>加减&nbsp;</td><td>+  -&nbsp;</td> <td>从左到右&nbsp;</td> </tr>
<tr> <td>移位&nbsp;</td> <td>&lt;&lt; &gt;&gt;&nbsp;</td> <td>从左到右&nbsp;</td> </tr> 
<tr> <td>关系&nbsp;</td><td>&lt; &lt;=  &gt; &gt;=&nbsp;</td> <td>从左到右&nbsp;</td> </tr>
<tr> <td>相等&nbsp;</td> <td>==  !=&nbsp;</td> <td>从左到右&nbsp;</td> </tr> 
<tr> <td>位与 AND&nbsp;</td><td>&amp;&nbsp;</td> <td>从左到右&nbsp;</td> </tr> 
<tr> <td>位异或 XOR&nbsp;</td> <td>^&nbsp;</td> <td>从左到右&nbsp;</td></tr> 
<tr> <td>位或 OR&nbsp;</td> <td>|&nbsp;</td> <td>从左到右&nbsp;</td></tr> 
<tr> <td>逻辑与 AND&nbsp;</td><td>&amp;&amp;&nbsp;</td> <td>从左到右&nbsp;</td></tr>
<tr> <td>逻辑或 OR&nbsp;</td> <td>||&nbsp;</td> <td>从左到右&nbsp;</td></tr> 
<tr> <td>条件&nbsp;</td><td>?:&nbsp;</td> <td>从右到左&nbsp;</td> </tr>
<tr> <td>赋值&nbsp;</td> <td>=  +=  -=  *=  /=  %=&gt;&gt;=  &lt;&lt;=  &amp;=  ^=   |=&nbsp;</td><td>从右到左&nbsp;</td></tr>
<tr> <td>逗号&nbsp;</td> <td>,&nbsp;</td> <td>从左到右&nbsp;</td></tr> 
</table>
<h3>实例</h3>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">

<span style="color: #05a; font-weight: bold;">using</span> <span style="color: #696969;">System</span><span style="color: #008000;">;</span><br />
<br />
<span style="color: #05a; font-weight: bold;">namespace</span> OperatorsAppl<br />
<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; <br />
&nbsp; &nbsp;<span style="color: #6666cc; font-weight: bold;">class</span> Program<br />
&nbsp; &nbsp;<span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #05a; font-weight: bold;">static</span> <span style="color: #6666cc; font-weight: bold;">void</span> Main<span style="color: #008000;">&#40;</span><span style="color: #6666cc; font-weight: bold;">string</span><span style="color: #008000;">&#91;</span><span style="color: #008000;">&#93;</span> args<span style="color: #008000;">&#41;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #6666cc; font-weight: bold;">int</span> a <span style="color: #008000;">=</span> <span style="color: Maroon;">20</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #6666cc; font-weight: bold;">int</span> b <span style="color: #008000;">=</span> <span style="color: Maroon;">10</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #6666cc; font-weight: bold;">int</span> c <span style="color: #008000;">=</span> <span style="color: Maroon;">15</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #6666cc; font-weight: bold;">int</span> d <span style="color: #008000;">=</span> <span style="color: Maroon;">5</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span style="color: #6666cc; font-weight: bold;">int</span> e<span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;e <span style="color: #008000;">=</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">+</span> b<span style="color: #008000;">&#41;</span> <span style="color: #008000;">*</span> c <span style="color: #008000;">/</span> d<span style="color: #008000;">;</span> &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// ( 30 * 15 ) / 5</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;(a + b) * c / d 的值是 {0}&quot;</span>, e<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;e <span style="color: #008000;">=</span> <span style="color: #008000;">&#40;</span><span style="color: #008000;">&#40;</span>a <span style="color: #008000;">+</span> b<span style="color: #008000;">&#41;</span> <span style="color: #008000;">*</span> c<span style="color: #008000;">&#41;</span> <span style="color: #008000;">/</span> d<span style="color: #008000;">;</span> &nbsp; <span style="color: #696969; font-style: italic;">// (30 * 15 ) / 5</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;((a + b) * c) / d 的值是 {0}&quot;</span>, e<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;e <span style="color: #008000;">=</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">+</span> b<span style="color: #008000;">&#41;</span> <span style="color: #008000;">*</span> <span style="color: #008000;">&#40;</span>c <span style="color: #008000;">/</span> d<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span> &nbsp; <span style="color: #696969; font-style: italic;">// (30) * (15/5)</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;(a + b) * (c / d) 的值是 {0}&quot;</span>, e<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;e <span style="color: #008000;">=</span> a <span style="color: #008000;">+</span> <span style="color: #008000;">&#40;</span>b <span style="color: #008000;">*</span> c<span style="color: #008000;">&#41;</span> <span style="color: #008000;">/</span> d<span style="color: #008000;">;</span> &nbsp; &nbsp;<span style="color: #696969; font-style: italic;">// &nbsp;20 + (150/5)</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span><span style="color: #a11;">&quot;a + (b * c) / d 的值是 {0}&quot;</span>, e<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Console<span style="color: #008000;">.</span><span style="color: #05a;">ReadLine</span><span style="color: #008000;">&#40;</span><span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span><br />
&nbsp; &nbsp; &nbsp; <span style="color: #008000;">&#125;</span><br />
&nbsp; &nbsp;<span style="color: #008000;">&#125;</span><br />
<span style="color: #008000;">&#125;</span><br />

</div>
</div>
<p>当上面的代码被编译和执行时，它会产生下列结果：</p>
<pre class="result">
(a + b) * c / d 的值是 90
((a + b) * c) / d 的值是 90
(a + b) * (c / d) 的值是 90
a + (b * c) / d 的值是 50
</pre>

<p><strong>算术运算符和赋值运算符的优先级：</strong></p>

<div class="example"><h2 class="example">实例</h2> <div class="example_code">
<span style="color: #6666cc; font-weight: bold;">int</span> a <span style="color: #008000;">=</span> <span style="color: Maroon;">10</span>, b <span style="color: #008000;">=</span> <span style="color: Maroon;">5</span>, c <span style="color: #008000;">=</span> <span style="color: Maroon;">2</span><span style="color: #008000;">;</span><br />
<span style="color: #6666cc; font-weight: bold;">int</span> result <span style="color: #008000;">=</span> a <span style="color: #008000;">+</span> b <span style="color: #008000;">*</span> c<span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 先计算乘法，再计算加法</span><br />
Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span>result<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 输出20</span><br />
<br />
result <span style="color: #008000;">=</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">+</span> b<span style="color: #008000;">&#41;</span> <span style="color: #008000;">*</span> c<span style="color: #008000;">;</span> &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// 先计算加法，再计算乘法</span><br />
Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span>result<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 输出30</span><br />
<br />
a <span style="color: #008000;">+=</span> b <span style="color: #008000;">*</span> c<span style="color: #008000;">;</span> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// 先计算乘法，再执行加法赋值</span><br />
Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span>a<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span> &nbsp; &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// 输出20</span><br />
</div></div>
<p><strong>逻辑运算符的优先级：</strong></p>
<div class="example"><h2 class="example">实例</h2> <div class="example_code">
<br />
<span style="color: #6666cc; font-weight: bold;">bool</span> a <span style="color: #008000;">=</span> <span style="color: #05a; font-weight: bold;">true</span>, b <span style="color: #008000;">=</span> <span style="color: #05a; font-weight: bold;">false</span>, c <span style="color: #008000;">=</span> <span style="color: #05a; font-weight: bold;">true</span><span style="color: #008000;">;</span><br />
<span style="color: #6666cc; font-weight: bold;">bool</span> result <span style="color: #008000;">=</span> a <span style="color: #008000;">||</span> b <span style="color: #008000;">&amp;&amp;</span> c<span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 先计算与运算，再计算或运算</span><br />
Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span>result<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 输出true</span><br />
<br />
result <span style="color: #008000;">=</span> <span style="color: #008000;">&#40;</span>a <span style="color: #008000;">||</span> b<span style="color: #008000;">&#41;</span> <span style="color: #008000;">&amp;&amp;</span> c<span style="color: #008000;">;</span> &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// 先计算或运算，再计算与运算</span><br />
Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span>result<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 输出true</span><br />
<br />
result <span style="color: #008000;">=</span> a <span style="color: #008000;">||</span> <span style="color: #008000;">&#40;</span>b <span style="color: #008000;">&amp;&amp;</span> c<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span> &nbsp; &nbsp; <span style="color: #696969; font-style: italic;">// 先计算与运算，再计算或运算</span><br />
Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span>result<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 输出true</span><br />
</div></div>
<p><strong>条件运算符的优先级：</strong></p>

<div class="example"><h2 class="example">实例</h2> <div class="example_code">
<span style="color: #6666cc; font-weight: bold;">int</span> a <span style="color: #008000;">=</span> <span style="color: Maroon;">10</span>, b <span style="color: #008000;">=</span> <span style="color: Maroon;">5</span><span style="color: #008000;">;</span><br />
<span style="color: #6666cc; font-weight: bold;">string</span> result <span style="color: #008000;">=</span> a <span style="color: #008000;">&gt;</span> b <span style="color: #008000;">?</span> <span style="color: #a11;">&quot;a大于b&quot;</span> <span style="color: #008000;">:</span> <span style="color: #a11;">&quot;a不大于b&quot;</span><span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 先判断大小关系，再执行条件语句</span><br />
Console<span style="color: #008000;">.</span><span style="color: #05a;">WriteLine</span><span style="color: #008000;">&#40;</span>result<span style="color: #008000;">&#41;</span><span style="color: #008000;">;</span> &nbsp;<span style="color: #696969; font-style: italic;">// 输出&quot;a大于b&quot;</span><br />
</div></div><p>
<strong>注意：</strong>由于括号可以改变运算符优先级，所以在实际应用中建议尽可能使用括号来明确运算顺序，提高代码的可读性和准确性。</p>			<!-- 其他扩展 -->
						
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	<ol class="commentlist">
		<li class="comment even thread-even depth-1" id="comment-23406"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;沐水杉</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;248***224@qq.com</p></div><div id="runoobvote-id-23406" data-commid = "23406" class="upvotejs"><a class="upvote"></a> <span class="count">45</span></div></div><div class="comt-main" id="div-comment-23406"><p><span class="marked">&，|，^ </span>除了用于位运算，还可以用于逻辑运算，分别对应与，或，异或。</p>
<p><strong>^ 运算符</strong>针对整型类型和 bool 预定义了二元 ^ 运算符。 对于整型类型，^ 会计算其操作数的按位异或。 对于 bool 操作数，^ 计算其操作数的逻辑异或；即，当且仅当其一个操作数为 true 时，结果才为 true。</p>


<pre>Console.WriteLine(true ^ false);  // 返回 true
Console.WriteLine(false ^ false);  // 返回 false
Console.WriteLine(true ^ true);  // 返回 false</pre>


<p><strong>| 运算符</strong>针对整型类型和 bool 预定义了二元 | 运算符。 对于整型类型，| 会计算其操作数的按位 OR。 对于 bool 操作数，| 会计算其操作数的逻辑 OR；即，当且仅当其两个操作数皆为 false 时，结果才为 false。</p>

<pre>Console.WriteLine(true | false);  // 返回 true
Console.WriteLine(false | false); // 返回 false</pre>


<p><strong>& 运算符</strong>为整型类型和 bool 预定义了二元 & 运算符。 对于整型类型，& 计算其操作数的逻辑按位 AND。 对于 bool 操作数，& 计算其操作数的逻辑 AND；即，当且仅当其两个操作数皆为 true 时，结果才为 true。</p>


<pre>Console.WriteLine(true &amp; false);  // 返回 false
Console.WriteLine(true &amp; true);   // 返回 true</pre>


<p>其中&，|的运算结果与&&，||完全相同，但&&和||的性能更好。因为&&和||都是检查第一个操作数的值，如果已经能判断结果，就根本不处理第二个操作数。</p>

<p>比如：</p>

<pre>bool a = true;               
bool b = false;              
bool c = a || b;</pre>

<p>检查第一个操作数a时已经得出c为true，就不用再处理第二个操作数b了。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">沐水杉</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;沐水杉</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;248***224@qq.com</p></div></span>5年前 (2018-01-23)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-42463"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;宅仙儿</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;135***77427@163.com</p></div><div id="runoobvote-id-42463" data-commid = "42463" class="upvotejs"><a class="upvote"></a> <span class="count">61</span></div></div><div class="comt-main" id="div-comment-42463"><p><strong>可空类型修饰符 ?</strong></p>

<p>引用类型可以使用空引用表示一个不存在的值，而值类型通常不能表示为空。 </p>

<p>例如：<span class="marked">string str=null;</span> 是正确的，<span class="marked">int i=null;</span> 编译器就会报错。 </p>

<p>为了使值类型也可为空，就可以使用可空类型，即用可空类型修饰符 <span class="marked">?</span> 来表示，表现形式为 <span class="marked">T?</span> 。</p>

<p>例如：<strong>int?</strong> 表示可空的整形，<strong>DateTime?</strong> 表示可为空的时间。 </p>

<p><strong>T?</strong> 其实是 System.Nullable(泛型结构）的缩写形式，也就意味着当你用到 <strong>T？</strong>时编译器编译时会把T？编译成 System.Nullable 的形式。 </p>

<p>例如：<span class="marked">int?</span>，编译后便是 System.Nullable 的形式。</p>

<p><strong>三元（运算符）表达式 ?:  </strong></p>

<p>例如：<span class="marked">x?y:z</span> 表示如果表达式 x 为 true，则返回 y；如果 x 为 false，则返回 z，是 <span class="marked">if{}else{}</span> 的简单形式。</p>

<p><strong>空合并运算符 ?? </strong></p>

<p>用于定义可空类型和引用类型的默认值。</p>

<p>如果此运算符的左操作数不为 null，则此运算符将返回左操作数，否则返回右操作数。</p>

<p>例如：<strong>a??b</strong> 当 a 为 null 时则返回 b，a 不为 null 时则返回 a 本身。 </p>

<p>空合并运算符为右结合运算符，即操作时从右向左进行组合的。</p>

<p>如: <span class="marked">a??b??c</span> 的形式按  <strong>a??(b??c)</strong> 计算。</p>

<p><strong>NULL 检查运算符 ?. </strong></p>

<pre>int? firstX = points?.FirstOrDefault()?.X;</pre>
<p>从这个例子中我们也可以看出它的基本用法：如果对象为 NULL，则不进行后面的获取成员的运算，直接返回 NULL。</p>

<p>需要注意的是，由于 <span class="marked">?.</span> 运算符返回的可以是 NULL，当返回的成员类型是 struct 类型的时候， <span class="marked">?.</span> 和 <strong>.</strong> 运算符的返回值类型是不一样的。</p>

<pre>Point p = new Point(3, 2); 
Console.WriteLine(p.X.GetType() == typeof(int));        //true
Console.WriteLine(p?.X.GetType() == typeof(int?));      //true</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">宅仙儿</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;宅仙儿</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;135***77427@163.com</p></div></span>4年前 (2019-05-05)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-44907"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;无名小卒</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;pea***butterli@163.com</p></div><div id="runoobvote-id-44907" data-commid = "44907" class="upvotejs"><a class="upvote"></a> <span class="count">61</span></div></div><div class="comt-main" id="div-comment-44907"><p>C# 是用 <strong>&lt;&lt;(左移)</strong> 和 <strong>&gt;&gt;（右移）</strong> 运算符是用来执行移位运算。</p><p>左移 (&lt;&lt;)：将第一个操作数向左移动第二个操作数指定的位数，空出的位置补 0。</p><p>左移相当于乘. 左移一位相当于乘2;左移两位相当于乘4;左移三位相当于乘8。</p><pre>
x&lt;&lt;1= x*2
x&lt;&lt;2= x*4
x&lt;&lt;3= x*8
x&lt;&lt;4= x*16
</pre><p>同理, 右移即相反：</p><p>右移 (&gt;&gt;)：将第一个操作数向右移动第二个操作数所指定的位数，空出的位置补 0。</p><p>右移相当于整除. 右移一位相当于除以 2;右移两位相当于除以 4;右移三位相当于除以 8。</p><pre>
x&gt;&gt;1= x/2
x&gt;&gt;2= x/4
x&gt;&gt;3= x/8
x&gt;&gt;4= x/16
</pre><p></p><p>因为位移比乘除速度快，对效率要求高，而且满足 2 的幂次方的乘除运方，可以采用位移的方式进行。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">无名小卒</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;无名小卒</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;pea***butterli@163.com</p></div></span>4年前 (2019-07-22)</div></div></li><!-- #comment-## -->
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		e.preventDefault();
		var noteContent = editor.getValue();
		// console.log(noteContent);
		noteContent = noteContent.replace(/<pre><code>/g,"<pre>");
		noteContent = noteContent.replace(/<\/code><\/pre>/g,"</pre>");
		
		// 系列化表单数据
		var comment_parent = 0;
		var is_user_logged_in = $("#is_user_logged_in").val();
		var comment_post_ID =  6591;
		var _wp_unfiltered_html_comment = $("#_wp_unfiltered_html_comment").val();
		var comment = noteContent;
		var author = $("#author").val();
		var url = $("#url").val();
		var email = $("#email").val();
		if(isBlank(author) && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入昵称！</p>').show();
		} else if(isBlank(email)  && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入邮箱！</p>').show();
		} else {
			// var formdata=commentform.serialize() + "&comment=" + noteContent ;
			// 添加状态信息
			statusdiv.html('<p>Processing...</p>').show();
			// 获取表单提交地址
			var formurl=commentform.attr('action');
			
			// 异步提交
			$.ajax({
					type: 'post',
					url: formurl,
					dataType:'json',
					data: {"comment_parent":comment_parent,"comment_post_ID":comment_post_ID, "_wp_unfiltered_html_comment":_wp_unfiltered_html_comment,"comment":comment,"url":url, "email":email,"author":author},
					error: function(XMLHttpRequest, textStatus, errorThrown){
					statusdiv.html('<p class="ajax-error" >数据不完整或表单提交太快了！</p>').show();
				},
				success: function(data, textStatus){
					if(data.errorno=="0") {
						$("#submit").prop('disabled', true);
						statusdiv.html('<p class="ajax-success" >笔记已提交审核，感谢分享笔记！</p>').show();
						alert('笔记已提交审核，感谢分享笔记！');
					}else{
						statusdiv.html('<p class="ajax-error" >'+data.msg+'</p>').show();
					}
					commentform.find('textarea[name=comment]').val('');
				}
			});
			setTimeout(function(){
		        $("#submit").prop('disabled', false);
		    }, 10*1000);
		}
		return false;

	});
	$(".comt-author").click(function() {
		href = $(this).children("a").attr("href");
		if(href.indexOf("/note/")!=-1) {
			var win = window.open(href, '_blank');
  			win.focus();
		}
	});
	$(".comt-meta span").hover(function(){
		$(this).children(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
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	});
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	},function(){
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	});
	*/
	//Upvote.create('runoobvote-id', {callback: vote_callback});
	var ajaxurl = 'https://www.runoob.com/wp-admin/admin-ajax.php';
	var callback = function(data) {
		//console.log($('#runoobvote-id').upvote('upvoted'));
		//console.log($('#runoobvote-id').upvote('downvoted'));
		//console.log(data);
		_vote_action = data.action;
		id_arr = data.id.split('-');
		um_id= id_arr[2];
		//console.log(um_id);
		
		var re = /^[1-9]+/;
		if (re.test(um_id)) { 
			var ajax_data = {
				_vote_action: _vote_action,
				action: "pinglun_zan",
				um_id: um_id,
				um_action: "ding"
			};
			//console.log(ajax_data);
			$.post(ajaxurl,ajax_data,function(status){
				//if(status.vote_num>999) {
				//	_voteHtml = '<span style="display: block; text-align: center;font-size: 20px; color: #6a737c; margin: 8px 0;">'+kFormatter(status.vote_num) +'</span>';
				//	$("#runoobvote-id-" + um_id + " .count").hide().after(_voteHtml);
				//}
				
			});
		}
	};
	if($('#comments').length && $('.upvotejs').length){
		$('.upvotejs').upvote({id: 6591, callback: callback});
	
		$.post(ajaxurl,{"action":"pinglun_zan","postid":6591},function(data){  
			$(data).each(function(key,value) {
				$("#runoobvote-id-" + value.commid + " .upvote").addClass(value.upvotejs_class);
				$("#runoobvote-id-" + value.commid + " .downvote").addClass(value.downvote_class);
				$("#runoobvote-id-" + value.commid + " .count").text(value.upvote_count);
			})
		},'json');
		
	}
	
	
});
function isBlank(str) {
    return (!str || /^\s*$/.test(str));
}
function kFormatter(num) {
	// return num;
    return Math.abs(num) > 999 ? Math.sign(num)*((Math.abs(num)/1000).toFixed(1)) + 'k' : Math.sign(num)*Math.abs(num)
}

</script>

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